اللهم أهلّه علينا باليمن والايمان والسلامة والاسلام والتوفيق لما تحب وترضى
Allāhumma ahillahu ʿalaynā bi-l-yumni wa-l-īmān wa-l-salāmati wa-l-islām wa-l-tawfīq limā tuḥibbu wa tarḍā
A prayer on sighting the new moon, asking that the month bring benefit, faith, security, Islam and success in what God loves.
What it means
Muslims say this prayer when they see the new crescent, which marks the start of a lunar month. It asks that the month bring blessing and faith, safety and Islam, and success in what pleases God. The Quran says that the new moons are “measures of time for people and for the hajj” (2:189). A prayer of this kind is reported from the Prophet in the collection of al-Tirmidhi. The Islamic calendar runs by the moon, so each month opens with a sighting and a supplication.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 63, listed as ALLAHUMMA AHILLAHU ‘ALAYNĀ BIL YUMNI WA AL ĪMĀNI WA AL SALĀMATI WA AL ISLĀMI WA AL TAWFĪQI LIMĀ TUḤIBBU WA TARḌĀ.. The definition is restated here.